Process of extracting copper or other metals from tailings or ores of such metals.



X R I "MA j UNITED ETATES PATENT PROCESS OF EXTRACTING COPPER OR OTHER METALS FROM TAlLlNGS 0R ORES OF SUCH METALS.

EDWARD FINK, OF MILWAUKEE, \VISCONSIN.

SlECIFICATION forming part of Letters Patent No. 653,414, dated July 10, 1900.

" Application filed September 23 1899.

To all whom it ntmy concern:

Be it known that I, EDWARD FINK, a citizen of'the United States, residing at Milwaukee, in the county of Milwaukee and State of Wisconsin, have invented a certain new and useful Process of Extracting Copper or Other Metals from 'llailings or Ores of Such Metals, of which the following is a specification.

The main object olf my invention is to expeditiously and economically extract copper and other metals from tailings and ores containingrsuch metals.

I have discovered that copper and other metals can be extracted from railings or ores hoth rapidly and economically bysubjccting the railings or ores to the action of a solution containingsult gicacid and some substance or substanceEhapable of libcrati ng nitric oxid eitlnr through its or their action upon the sulfuric acid alone or through the combined action of such substances upon suliuric acid and metallic copper or sullld of copper. The substances best adapted f or this purpose are metallic nitrates, nitrites, or free nitric or nitrous acid.

In case a nitrate is used in the treatment of tailings or ores containing metallic copper the chemical reactions are expressed by the following equation:

and in case a nitrate is used in treating tailings or ores Containing sulfid of copper the chemical reactions are expressed in the following equation: i

mimo -toons -ninso.=am,so,+tcuso.ias snnl {-INO. The nitric oxid formed upon coming in contact with air is at once oxidized and converted into a higher oxid or oxids, principally to nitrogen poroxid, (NO

The foregoing reactions may be expressed by the following equation In the presence of moisture these higher oxids rapidly corrode copper and other metals or metallic .sul lids and are themselves reduced to nitric oxid. It is probable that at least a portion of the nitrogen peroxid is converted to a mixture of nitric and nitrous acids upon coming in contact with nioistiu-o, according into nitric oxid and is thus rendered capable Serial No. 731,463. (No specimens.)

to the reactions expressed in the following i n. e'qu ation i 2No,+n,o=1mo,+nno,. f) H. .lhese acids, if produced, will act upon the copper or other metal in the usual manner. In any event the nitric oxid formed is allernately oxidized and reduced or reconverted of oxidizing a large amount of copper or other metal, thereby making the process a continuous one. The foregoing operations are pref erably performed in a closed or substan tiallyclosed vessel con taining an excess of air at or above atmospheric pressure. The relative quantities of sulfuric acid and nitrate, nitrite, or free nitric or nitrous acid required depend upon the percentage of copper or other metal contained in the tailings or ore,

as well as upon the nature of the tailings or 7 ores themselves. For taili ngs or oro containing one percent. of copper the following proportions per ton of taili has or ore have proved very ellicient and satisfactory: sulfuric acid, thirty pounds; sodium nitrate, live pounds; water, fifty pounds. The sulfuric acid and water are first mixed, preferably in the vossol containing the ore, and the sodium ni trato is then added. The action of the sulfuric acid upon the water produces sul'lieient heat to cause a very rapid oxidation of. the copper upon the addiii on ol. the. nitrate or nitrite, and

it is desirable to keep the mixture at a temperatu re of from (30 to 100 Fahrenheit,as this temperature is suflicient to cause a rapid so 8 5 lntion of the copper. The desired. tempera ture may be produced and maintained by means of a steam jacket or coil orby othersuitable means. The tailin gs or ore is preferably subjected alternately to the oxidizing influ- 0 once of the fumes of the pcroxid orhigher oxidsof nitrogen and to thesolventaction of the sulfuric acid, and to this end the process may be conveniently performed in a rotary drum or apparatus, by which the tailings or ore will he suoeessivel y immersed in the solution and subjected to the action of the nitrous fumes confined ahovo the solution, since the copper contained in tho tailing's or ore is more rapidly oxidized and dissolvcflin this way than ii. would be it ilI'wei-e coi'itainTnlih' a stationary roceptmdo. Any other form of apparatus suitable for securing the results above mentioned may, however, be employed.

Then the metal contained in the failings or ore has been oxidized and dissolved in the solution, asabove explained,tl 1e solution is decanted and the contents of the vessel or receptaclc leached outwith water. The sulfate gll C O11D Ql QQJJt-il l (il in tl 1 e combined sol ufib'ns isrthen -5511 tatedivith iitaniairafi fifnm usualway orismm'y'mmnknown method. Before the drum or receptacle in which the firststeps of the process are performed is opened the remaining gases-or nitrous fumes confined therein are preferably conducted into another drum or receptacle in which other tailiugs or ore is about to be treated, or they may be forced into a solution of caustic soda, by which they will be absorbed,thus forming sodium nitrate or nitrite, or a mixture of both, which may be utilized at any time in the initial treatment of other tailings or ores.

I have explicitly described my improved process more particularly with respect to the treatment of copper failings and ores; but it may be advantageously employed in the treatment of tailings or ores of other-metals.

I claim- I 1. The process of extracting copper and other metals from tailings or ores of such metals, which consists in subjecting the tailings or ore to the action of a solution containing sulfuric acid and to the action of an oxid or oxids of nitrogen, in the presence of air or oxygen under pressure, whereby the metal is oxidized and dissolved and the oxid or oxids;

of nitrogen areconverted alternately'iuto a lower and a higher oxid or oxids, and finally separating the solution from the earthy matter of the failings or ore and separating the metal from the solution, substantially as and for the purposes set forth.

2. The process of extracting copper and other metals from tailings or ores of such metals, which consists in subjecting the tailings or ore to the action of a solution containing sulfuric acid and to the action of an oxid or oxids of nitrogen con fined in the presence of the solution, whereby the metal contained in the taili'ngs or ore is oxidized and dissolved, supplying air or oxygen under pressure to the nitrous fumes from which oxygen has been taken by the metal, and reconverting them into a higher oxid or oxids' to be again re duced to a lower oxid or oxids by acting on the tailings or ores, until the metal is extracted therefrom, and finally separating the earthy matter and the metal from the solution, substantially as and for the purposes set forth.

The process of extracting copper and other metals from failings or ores containing such metals, which consists in subjecting the tailings or ore alternately to the actionof a solution containing sulfuric acid and to the action. of an oxid or oxids of nitrogen confined in the presence of the solution and capable ofoxidizing the metal contained in the tailings or ore, supplying air or oxygen under pressure to the nitrous fumes from which oxygen has been taken and thereby reconvetting theminto a higher oxid or oxids to further act on the failings or ore, until the metal is dissolved in the solution, and finally separating the matrix or earthy matter and the metal from the solution, substantially as and for the purposes set forth.

4. The' process of extracting copper and other metals from tailings or ores-containing such metals, which consists in subjecting the tailings or ore to the action of asolutioneontaining sulfuric acid and to the action of a corrosive oxid of nitrogen, confining the nitrous fumes given off by the solution in the presence of the solution and supplying air or oxygen under pressure to such fumes, whereby they are converted into a higher oxid or oxids capable of again imparting oxygen to the metal contained in the tailin gs or ore until the metal is extracted therefrom and dissolved in the solution, separating the matrix or earthy matter and the metal from the solution, and finally utilizing the remaining nitrous fumes for treating other tailings or ore, substantially as and for the purposes set forth. I

5. The process of extracting copper and other metals from tailings or ores containing such metals, which consists in subjecting the tailings or ore to the action of a solution containing sulfuric acid and a substance capable of liberating nitric oxid, con fl n i mg the nitrous fumes given off from the solution in the presonce of the solution, supplying air or oxygen under pressure to such fumes whereby the lower oxids are repeated] y converted into the higher oxids of nitrogen capable of imparting oxygen to the metal contained in the tailings or ore and the process is rendered contin nous, until the metal has been dissolved in the solution, and finally separating the matrix or earthy matter and the metal from the solution, substantially as'andfor thcpnrposes set -.forth.

6. The process of extracting copper and other metals from tailings or ores containing such metals, which consists in subjecting the tailings or ore alternately to the action of a solution containing sulfuric acid and a substance capable of liberating nitric oxid, and to the action of nitrous fumes given oil: by and confined in the presence of such solution, supplying air or oxygen under pressure to such fumes and thereby converting them to a higher oxid or oxids before and after they act upon and impart oxygen to the failings or ore, and finally after the metal is extracted from the tailings or ore and dissolved in the solution, separating the matrix or earthy matter and the metal from the solution, substantially as and. for the purposes set forth.

7. The process of extracting copper and other metals from tailings or ores containing such metals, which consists in subjecting the the tailings or ore until the metal is extracted therefrom, separating the matrix or earthy material and the metal from such solution, and finally conducting off the remaining nitrous fumes for treating other tailin gs orore, substantially as and for the purposes set forth.

8. The process of extracting copper from tailings or ores of that metal, which consists in subjecting the tailings or ore to the action of a solution containing sulfuric acid and primarily a compound of nitrogen, capable of liberating nitric oxid, and to the action of a higher oxid or oxids produced and repeatedly reproduced by supplying air or oxygen under pressure to the liberated nitric oxid and to the higher oxid or oxids which have been reduced by acting on the tailings or ore and are confined in the presence of the solution until the metal contained in the tailings or ore is dissolved in the solution; separating the matrix or earthy m attcr from the solution,

and separating and precipitating the pepper;

from the solution, substaiiifially for the purposes set forth.

9. The process of extracting copper from tailings' or ores containing that metal, which consists in subjecting the tailings or ore alternately to the action of a solution containing sulfuric acid and primarily a compound of nitrogen, capable of liberating nitric oxid,

, ike-s and to the action of a higher oxid or oxids produced and repeatedly reproduced by sup- 4o plying air or oxygen under pressure to the liberated nitric oxid and tothe higher oxid or oxids whiehhave been reduced byvacting on the tailings or ore and are confined in the presence of the solution until the metal con- 45 tained in the tailings or ore is dissolved in the solution, then separating the matrix or earthy matter from the solution, and finally separating and precipitating the copper from the sol ntion, substantially as and for the pur- 50 pesos set forth.

10. The process of extracting copper from tailings or ores containing that metal, which consists in subjecting the tailings or ore to the action of a solution containing sulfuric 5 5;

acid and primarily a compound of nitrogen, capable of liberating nitric oxid, and to the action of a higher oxid or oxids produced and repeatedly reproduced by supplying air,"

or oxygen under pressure to the liberated ni 6o trio oxid and to the higher oxid or oxids which have been reduced by acting on the tailings or ore and are confined in the pres once of the solution until the metal contained I in the tailings or ore is dissolged in the solu- ,6 5

tion, separating the matrix or earthy matter; from the solution, precipit from the solution, confining and conducting oilfther'eiiiai'nirignitrons fumes for the treat- '1 5 ment of other tailings or ore, substantially as 79 1 and for. the purposes set forth;

In witness whereof I hereto affix my signature in presence of two Witnesses.

ED\VARD FINK. 

